Decision affects about 38,000 property owners.

Auckland’s prized volcanic cones are in line for more protected view shafts, despite alarm that the unitary plan may allow developers to pierce what are now sacrosanct zones.

Councillors on Wednesday voted to put 35 new shafts up for public notification, and to remove seven others, in a separate exercise to the unitary planning process – which threatens to leave council officers with discretion from 2016 to approve higher buildings within sight lines of 11 volcanic peaks.

Their decision is expected to affect about 38,000 property owners in lengthening the list of view shafts to 87, compared with 59 introduced in 1976 by the Auckland Regional Authority after public fury over construction of The Pines apartment block high up against Mt Eden.

The wider public will also be allowed to make submissions on the proposal, which includes views of Mt Eden from the Domain and from the city end of Ponsonby Rd in additions to the list.

But some councillors, including heritage campaigner Sandra Coney, are alarmed that the draft unitary plan allows for an existing building height limit of 9m around the base of volcanic peaks to be breached by structures up to 20m high if council staff consider their visual integrity can be maintained.

Deputy Mayor Penny Hulse appealed unsuccessfully to the council’s regional development committee to wait until community consultations on the unitary plan are completed by May 31 before notifying changes to existing district plans incorporating the new view shafts.

She and a minority of four other councillors wanted the changes dealt with in the unitary planning process, which she is leading, to minimise public confusion and save almost $400,000 in extra costs.

“If people are not completely happy with what’s in the unitary plan, we’re not even halfway through the consultation yet and we will respond to the concerns people have,” she said. “We will amend the unitary plan and we will include protections of the cones – that’s a given.”

But her group was out-voted by 13 other committee members after Ms Coney said a regional policy statement calling for the new view shafts was promulgated more than a year ago and it was the council’s responsibility to amend existing planning documents to give effect to that.

“We need to be following due process under the Resource Management Act and not dragging the chain and lumping it in with the unitary plan,” Ms Coney said, adding that the committee had already voted last year for a dual process and it needed to keep faith with local boards, iwi and other stakeholders such as the Volcanic Cones Society.”

Mountain views

35 new volcano view shafts up for public notification 7 proposed to be removed 87 views shafts in total, if changes go ahead